MADISON The surface of cells and many biologically active molecules are studded with sugar structures that are not used to store energy, but rather are involved in communication, immunity and inflammation. In a similar manner, sugars attached to drugs can enhance, change or neutralize their effects, says Jon Thorson, a professor of pharmaceutical sciences at the University of Wisconsin-Madison School of Pharmacy.
Thorson, an expert in the attachment and function of these sugars, says that understanding and controlling them has major potential for improving drugs, but that researchers have been stymied because many novel sugars are difficult to create and manipulate. "The chemistry of these sugars is difficult, so we have been working on methods to make it more user friendly," he says.
Now, in a study published online in Nature Chemical Biology on Aug. 21, Thorson, graduate student Richard Gantt and postdoctoral fellow Pauline Peltier-Pain have described a simple process to separate the sugars from a carrier molecule, then attach them to a drug or other chemical. The process also causes a color change only among those molecules that have accepted the sugar. The change in color should support a screening system that would easily select out transformed molecules for further testing. "One can put 1,000 drug varieties on a plate and tell by color how many of them have received the added sugar," Thorson says.
Attached sugars play a key role in pharmacy, says Thorson. Not only can they change the solubility of a compound, but "there are transporters in the body that specifically recognize certain sugars, and pharmaceutical companies have taken advantage of this to direct molecules toward specific tissue or cell types. If we can build a toolbox that allows us to make these molecules on demand, we can ask, 'What will sugar A do when it's attached to drug B?'"
And although the new study was focused more on an improved technique rather than the a
|Contact: Jon S. Thorson|
University of Wisconsin-Madison